Gas-chromatographic results

Operational temperatures of 4—27°C are maintained. In this process the flavor components are concentrated in the retentate. A reduced alcohol product is obtained by adding back water to give the desired flavor impact. Typical gas chromatographic results, comparing unprocessed 80° proof whiskey with reverse osmosis processed 54° proof whiskey and diluted 54° proof whiskey, indicate good congener retention in the alcohol-reduced (RO) processed whiskey (Table 7). 

The columns labeled PI reflect the total of pyrethrin I and cinerin I just as in the AO AC procedure. The gas chromatographic results are in terms of the total amount of the mixture but were analyzed as the methyl ester of chrysanthemic acid. The present state of the determination of PII (pyrethrin II plus cinerin II) is not complete because of the erratic extractability of the dicarboxylic acids from the hydrolysis mixture. The gas chromatographic pattern is distinct and straightforward. As the extraction procedure for PII is improved, the gas chromatographic method will be more applicable. The present recovery of PII is in the range of 80 to 90%. The average of the values shown in Table II for PI is 98.0%. 

FIGURE 4.12 Gas chromatograph results for crude and refined LNAPL samples retrieved from a monitoring well network within a refinery tank farm. 

FIGURE 4.14 Additional aromatic compounds, sulfur, and sterene distribution based on gas chromatograph results. 

Empirical models are frequently applied in chemistry to relate experimental observations to physicochemical or thermodynamical quantities. This has extensively been used over several decades for the interpretation of experimental results obtained from gas phase adsorption processes and is still used to interpret the gas chromatographic results discussed in Chapter 7. These empirical procedures and correlations are outlined in Chapter 6 for a deeper understanding of one of the possible ways to interpret experimental findings from gas phase chemistry. 

Infrared analysis of the liquid fractions obtained by high vacuum pyrolysis in the authors laboratory confirmed the conclusion reached from quantitative gas chromatographic results. Significantly, cationic... 

Chromatograph 1 /xliter of each 50-ml. fraction from the alumina column. Tentatively identify the insecticides by their retention times. Composite the fractions on the basis of the gas chromatographic results, and concentrate each composite to 5.0 or 10.0 ml. in graduated centrifuge tubes. Determine the insecticides in each composite by gas chromatography and by comparison with a reference standard giving the same peak heights as the sample. 

In this chapter we wish to present some recent gas chromatographic results on the stability of the pore structure of the zeolite as the material undergoes these transformations. 

The pioneering paper on using molecular dynamics simulations to understand chiral gas chromatographic results was done by Konig s group [67]. Experimentally they found the S enantiomer of methyl-2-chloropropionate to be more retained on Lipodex D ([heptakis(3-0-acetyl-2,6-di-0-pentyl)-p-CD] coated on a capillary column) at 333 K. A large separation factor, a = 2.02, corresponding to a AAG = 2 kJ/mol i was observed and an attempt to discern the structural features of the transient complexes was made. 

The gas-chromatographic results have been used to determine the differences between the thermodynamic quantities of deuterated and protiated hydrocarbons with the help of the equation... 

The accuracy of the gas chromatographic results may be checked by comparison with those obtained through adsorption and diffusion of vapours in crystalline-amorphous polymers in gravimetric experiments [50-53]. 

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